Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
292 words
A method of operating a processor-controlled apparatus for controlling the operation of an internal combustion engine having a carburetor through which the air-fuel ratio of the air-fuel mixture supplied to the engine is controlled, and a controlled exhaust gas recirculation path having an exhaust gas recirculation valve for controllably recirculating exhaust gas from an exhaust pipe of said engine to an intake pipe for said carburetor, comprising the steps of: (a) storing, in memory, predetermined data defining prescribed operational control of said exhaust gas recirculation valve in accordance with prescribed engine operation conditions; (b) in response to at least one preselected sensed engine operation condition, including the position of the throttle of said carburetor, setting a maximum limit and a minimum limit on said prescribed operational control of said exhaust gas recirculation valve, such that said maximum and minimum limits become larger as the opening degree of said throttle valve becomes larger; (c) accessing from said memory data stored in step (a), based upon sensed engine operation conditions; (d) generating control signals for controlling the operation of said controlled exhaust gas recirculation valve in accordance with a prescribed relationship between data accessed from said memory in step (c) and said maximum and minimum limits set in step (b), such that the duty ratio of opening of said exhaust gas recirculation valve is between said maximum and minimum limits; (e) operating said controlled exhaust recirculation valve in accordance with the control signals generated in (d); and wherein step (d) comprises the steps of: (d1) comparing data accessed from memory with said maximum limit set in step (b), and (d2) in response to the value of said accessed data exceeding said maximum limit, generating said control signals on the basis of said maximum limit.
Claim 2
Independent Claim
292 words
A method of operating a processor-controlled apparatus for controlling the operation of an internal combustion engine having a carburetor through which the air-fuel ratio of the air-fuel mixture supplied to the engine is controlled, and a controlled exhaust gas recirculation path having an exhaust gas recirculation valve for controllably recirculating exhaust gas from an exhaust pipe of said engine to an intake pipe for said carburetor, comprising the steps of: (a) storing, in memory, predetermined data defining prescribed operational control of said exhaust gas recirculation valve in accordance with prescribed engine operation conditions; (b) in response to at least one preselected sensed engine operation condition, including the position of the throttle of said carburetor, setting a maximum limit and a minimum limit on said prescribed operational control of said exhaust gas recirculation valve, such that said maximum and minimum limits become larger as the opening degree of said throttle valve becomes larger; (c) accessing from said memory data stored in step (a), based upon sensed engine operation conditions; (d) generating control signals for controlling the operation of said controlled exhaust gas recirculation valve in accordance with a prescribed relationship between data accessed from said memory in step (c) and said maximum and minimum limits set in step (b), such that the duty ratio of opening of said exhaust gas recirculation valve is between said maximum and minimum limits; (e) operating said controlled exhaust recirculation valve in accordance with the control signals generated in (d); and wherein step (d) comprises the steps of: (d1) comparing data accessed from memory with said maximum limit set in step (b), and (d2) in response to the value of said accessed data exceeding said maximum limit, generating said control signals on the basis of said maximum limit.
Claim 3
Dependent Claim
19 words
A method according to claim 1, wherein said prescribed engine conditions comprises engine crankshaft speed and engine intake vacuum.
Claim 4
Dependent Claim
83 words
A method according to claim 1, wherein step (d) further comprises the steps of: (d1) comparing data accessed from memory with said maximum limit set in step (b), (d2) in response to the value of said accessed data not exceeding said maximum limit, comparing said accessed data with said minimum limit set in step (b), and (d3) in response to the value of said accessed data being less than said minimum limit, generating said control signals on the basis of said minimum limit.
Claim 5
Dependent Claim
82 words
A method according to claim 1, wherein step (d) further comprises the steps of: (d1) comparing data accessed from memory with said maximum limit set in step (b), (d2) in response to the value of said accessed data not exceeding said maximum limit, comparing said accessed data with said minimum limit set in step (b), and (d3) in response to the value of said minimum limit not exceeding said accessed data, generating said control signals on the basis of said accessed data.